. Elementary botany. Botany. LIVERWORTS: MARCHANTIA. '53 attachment at the base of the archegonium. Soon, as shown in fig. 185 at the right, the outer portion of the sporogonium begins to differentiate into the cells which form the elaters and those which form spores. These lie in radiating lines side by side, and form what is termed thearchesporium. Each fertile cell forms lour spores just as in riccia. They are thus called tin mother cells of the spores, or spore mother cells. 326. How marchantia multiplies. New plants of marchantia are formed by the germination of the spores, and growth of
. Elementary botany. Botany. LIVERWORTS: MARCHANTIA. '53 attachment at the base of the archegonium. Soon, as shown in fig. 185 at the right, the outer portion of the sporogonium begins to differentiate into the cells which form the elaters and those which form spores. These lie in radiating lines side by side, and form what is termed thearchesporium. Each fertile cell forms lour spores just as in riccia. They are thus called tin mother cells of the spores, or spore mother cells. 326. How marchantia multiplies. New plants of marchantia are formed by the germination of the spores, and growth of the same to the thallus. The plants may also be multiplied by parts of the old ones breaking away by the action of strong currents of water, and when they lodge in suitable places grow into well-formed plants. As the thallus lives from year to year and continues to grow and branch the older portions die off, and thus sepa- rate plants may be formed from a former single one. 327. Buds, or gemmae, of marchantia.—But there is another way in which marchantia multiplies itself. If we examine the upper surface of such a. Fig. 186. Marchantia plant with cupules and gemmae ; rhizoids below. plant as that shown in fig. 186, we will see that there are minute cup- shaped or saucer-shaped vessels, and within them minute green bodies. If we examine a few of these minute bodies with the microscope we will see that they are flattened, biconvex, and at two opposite points on the margin there i> an indentation similar to that which appears at the growing end of the old marchantia thallus. These are the growing points of these little bud-. When the\- free themselves from the cups they come to lie on one. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Atkinson, George Francis, 1854-1918. New York, H. Holt and company
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